docs: def as_sql(self, qn, connection):
          """
          Create the proper SQL fragment. This inserts something like
          "(T0.flags & value) != 0".
  
          This will be called by Where.as_sql()
          """
          engine = connection.settings_dict['ENGINE'].rsplit('.', -1)[-1]
          if engine.startswith('postgres'):
              XOR_OPERATOR = '#'
          elif engine.startswith('sqlite'):
              raise NotImplementedError
          else:
              XOR_OPERATOR = '^'
  
          if self.bit:
              return ("%s.%s | %d" % (qn(self.table_alias), qn(self.column), self.bit.mask),
                      [])
          return ("%s.%s %s %d" % (qn(self.table_alias), qn(self.column), XOR_OPERATOR, self.bit.mask),
                  [])